Which comes first, bench size or height?

Answer: Size. It follows the envelope and needs a new top to change; height follows elbow percentiles and moves 100 mm with feet and a footrest.

Profile or welded steel for a Case Assembly Workstation frame?

Answer: It depends on change frequency. A 40 × 40 × 2 mm profile frame rebuilds a station in 2 hours; welded steel costs 30% less but stops the line half a day.

Does the 82 second takt hold at one station?

Answer: Stations vary 10 to 15 seconds; 20 seconds marks the bottleneck. Size bench and bins for that station or it stays short.

How is pressure drop checked on site?

Answer: Fit class 0.4 gauges at the filter outlet and the tool, run both, read the gap. Within 0.03 MPa passes; beyond it, upsize the drop.

Sign off lighting at 300 lx or 500 lx?

Answer: Match the task. Closing a lid passes at 300 lx; aligning holes or judging a gasket crease needs 500 lx and 750 lx inside the cavity.

From 46 kg Load to 500 lx: Sizing a Case Assembly Workstation

Quick answer: A Case Assembly Workstation is sized by three inputs — loaded mass, envelope and takt — and the rest is arithmetic: a 46 kg case on an 82 second takt gives a 900 × 700 mm bench, a 300 kg frame and 500 lx at the face.

Three Numbers Set the Case Assembly Workstation
Bench Size From the Envelope
Height and Legroom From Elbow Height
Rack Pitch From Consumption
Air and Power: Pressure, Flow, Ports
Light at the Assembly Face
FAQ

1. Three Numbers Set the Case Assembly Workstation

Three values fix a Case Assembly Workstation before a line is drawn: loaded mass, outer envelope, takt. Take a moulded case of 620 × 460 × 230 mm, 46 kg when full, 320 units a shift, 82 seconds per unit. Those three produce a dozen derived values.

Mass sets structure. Spread 46 kg over a 900 mm span, but an operator leans on the case while a latch clicks; at 1.5 times the load is 69 kg, so the frame is rated 300 kg static and 120 kg dynamic.

Envelope sets the bench and takt sets the rack: 620 × 460 mm forces 900 × 700 mm of surface, and 82 seconds fixes a refill every 15 minutes.

Input	Value	Derived parameter	Window
Loaded mass	46 kg	Frame rating, top thickness	300 kg static or more
Envelope	620 × 460 × 230 mm	Bench width and depth	Not under 900 × 700 mm
Output	320 units a shift	Takt, bin size, refills	60 to 120 seconds

2. Bench Size From the Envelope

Extra area does not improve a Case Assembly Workstation bench. The case is 620 mm long, so 140 mm a side makes the bench 900 mm wide; it is 460 mm deep, so 120 mm front and back makes 700 mm. The margin is working room: fingers need 25 mm under the bottom edge, corners swing a 60 mm arc when the case turns.

Case Assembly Workstation: close-up of a black case lid, arch handle across the top, a square latch at each end, white bench below

The top is 25 mm plywood with a 2 mm anti-static skin. Across 900 mm the centre must not deflect past 1.5 mm; beyond that the case levels itself and one hand steadies it, costing 7 seconds a unit. The Case Assembly Workstation frame is 40 × 40 × 2 mm profile on 4 posts, loaded at 71 kg against a 300 kg rating.

Member	Section	Capacity	Failure mode
Post	40 × 40 × 2 mm	400 kg axial	Foot sinks, top tilts
Cross member	40 × 40 × 2 mm, 2 off	1 mm at 50 N side push	Bench shakes
Top	25 mm plywood	1.5 mm at 900 mm	Case rotates, holes miss

3. Height and Legroom From Elbow Height

Height is derived, not remembered. GB/T 10000 puts male elbow height at 954 to 1096 mm, female at 899 to 1021 mm. Precision work needs a downward view, so the top sits 50 to 100 mm below the elbow, at 950 to 1000 mm; general assembly drops to near 900 mm.

Operators differ by 140 mm in stature but the top holds one height, so the gap closes at the floor with a 100 mm footrest. A seated place runs a 720 to 760 mm top and legroom 620 mm high, 450 mm deep, 700 mm wide.

Task	Posture	Elbow	Bench
Precision fitting	Standing	954 mm	950 to 1000 mm
General assembly	Standing	1024 mm	900 to 950 mm

4. Rack Pitch From Consumption

Racks on a Case Assembly Workstation follow consumption, not wall space. Each unit takes 18 M6 screws and a box holds 200, so one box covers 11 units; at 82 seconds it lasts 15 minutes and a shift needs 4 refills. More than 6 means the box is too small, and picking costs about 8% of output.

Case Assembly Workstation: one corner of a black lid, a square latch gripping the rim, four raised ribs on its face, handle passing above

Pitch is the tallest bin plus 40 mm. Bins here are 210 mm, so pitch is 250 mm; 5 tiers reach 1250 mm, plus a 150 mm plinth, putting the top level at 1400 mm, below the shoulder. A sixth tier would sit at 1650 mm, an overhead reach, so it goes. Depth is 400 mm, and each tier carries 60 kg on 30 × 30 × 1.5 mm posts.

5. Air and Power: Pressure, Flow, Ports

An air screwdriver wants 0.5 to 0.6 MPa and draws 0.30 m³/min. Two at once need an 8 mm main and 6 mm drops, losing no more than 0.03 MPa. At 0.05 MPa M6 screws stop reaching 8 N·m, a batch out of tolerance.

A Case Assembly Workstation filter unit holds 5 µm and drains once a shift; quick couplings sit 200 mm above the top and 250 mm in from the edge.

Power is a 220 V, 10 A duplex outlet 150 mm under the bench, behind 30 mA protection tripping in 0.1 s, earth below 4 Ω. The anti-static surface reads 1 MΩ to 1000 MΩ. Flight cases add sling requirements, see airdrop case limits.

6. Light at the Assembly Face

The Case Assembly Workstation face needs 300 lx for general assembly and 500 lx for precision, floors from GB 50034. The cavity is 230 mm deep and overhead light never reaches it, so a 4000 K, Ra 85 strip sits 1200 mm above the bench and lifts the floor to 750 lx.

Keep cut-off at 30 degrees and flicker under 8%; above 6000 K a gasket crease disappears. Read a meter on a 1 m grid, 9 points, lowest over highest above 0.7. One-sided strips drop the far end to 210 lx, where missed latches come from.

Conclusion

Three inputs — 46 kg, 620 × 460 × 230 mm, 82 seconds — carry bench, frame, height, rack, air and light in one chain, and every link can be measured on the floor. Revisions fall from 3 rounds to 1. Specifications come from load and takt, not a catalogue, which is why a Case Assembly Workstation deserves the arithmetic first.

This article discusses only the container (case body) side of specifications and design intent, and does not cover any handling, loading or use of the contents.